Twenty trucks were unable to transport aid to Palestinian civilians in the besieged Gaza Strip on Tuesday, the United Nations said as US President Joe Biden dubbed humanitarian efforts to deliver help via a crossing from Egypt as “not fast enough.”

“We hope the materials can enter Gaza tomorrow,” said UN aid spokesperson Eri Kaneko. She did not say why the trucks had not been able to cross into Gaza from Egypt on Tuesday.

The United States is negotiating with Israel, Egypt and the United Nations to try and create a delivery mechanism to get aid into Gaza. They are wrangling over procedures for inspecting the aid and bombardments on the Gaza side of the border.

When asked by reporters at the White House on Tuesday whether aid was getting to Gaza as fast as needed, Biden said: “not fast enough.”

Rafah is the main crossing in and out of Gaza that does not border Israel. It has become the focus of efforts to deliver aid since Israel imposed a “total siege” of the enclave in retaliation for an attack by Hamas militants on Oct 7.

Since limited aid deliveries began on Saturday, 54 trucks have crossed into Gaza carrying food, medicine and water, which UN Secretary General Antonio Guterres described as “a drop of aid in an ocean of need.”

Senior UN aid official Lynn Hastings had earlier told the Security Council that 20 trucks were due to cross on Tuesday.

No fuel has been delivered. Israel is concerned about the possible diversion of fuel deliveries by Hamas. White House national security spokesman John Kirby on Tuesday described Israel’s concerns as legitimate.

“We still believe, just in general, that fuel needs to be able to get in to the people of Gaza,” he told reporters.

The United Nations has warned that its fuel reserves will run out within days. The UN agency providing aid to Palestinians in Gaza, UNRWA, warned on Tuesday that it would have to halt its operations on Wednesday night if there were no fuel deliveries.

“While we negotiate with the government of Israel as to how best to bring fuel into Gaza, we have 400,000 litres on trucks ready to go. This would provide fuel for approximately 2-1/2 more days,” Hastings told the Security Council.

Gaza reports record 24-hour death toll from Israeli bombing

The Palestinian health ministry said on Tuesday that Israeli air strikes had killed more than 700 Palestinians in Hamas-run Gaza overnight, and ministry spokesman Ashraf Al-Qidra said it was the highest 24-hour death toll in Israel’s two-week-old siege of the narrow strip.

United Nations agencies pleaded “on our knees” on Tuesday for emergency aid to be allowed unimpeded into Gaza, saying more than 20 times current deliveries were needed to support the Palestinian population after the two weeks of bombardment.

In a statement released on social media, the Palestinian health ministry said at least 5,791 Palestinians had been killed by Israeli bombardments since Oct. 7, including 2,360 children. Some 704 were killed in the previous 24 hours alone, it said.

Reuters could not independently verify the ministry figures.

The Israeli military said that it killed dozens of Hamas fighters overnight while hitting over 400 Hamas targets, but that it would take time to destroy the Islamist militant group whose deadly cross-border attack on Oct. 7 shocked Israel.

Macron told Prime Minister Benjamin Netanyahu that France stood “shoulder to shoulder” with Israel in its war with Hamas but that it must not fight “without rules”.

UN Secretary General Antonio Guterres pleaded on Tuesday for civilians to be protected, voicing concern about “clear violations of international humanitarian law” in Gaza.

The World Health Organization, in the latest of increasingly desperate UN appeals, called for “an immediate humanitarian ceasefire” to allow safe deliveries of food, medicines and fuel.

But there appeared to be little prospect of a ceasefire any time soon in the bloodiest chapter of the Israeli-Palestinian conflict for decades, with civilian suffering spreading.

Hospitals running out of fuel

All hospitals say they are running out of fuel to power their electricity generators, leaving them increasingly unable to treat the injured and ill. More than 40 medical centres have halted operations, a health ministry spokesman said.

The Israeli military reaffirmed it would not permit the entry of fuel to prevent Hamas from using it.

Call for immediate ceasefire

“We are all here together with a unified message that more violence is not the answer that all civilian lives are deserving of protection and that includes the lives of Palestinians living in Gaza,” Saudi Arabian Foreign Minister Faisal bin Farhan said after the UN Security Council meeting.

Palestinian Foreign Minister Riyad al-Maliki was also standing next to him.

“That is why we are standing here calling for an immediate ceasefire for an immediate lifting of the blockade on Gaza and for a return to a peace process and for a return to a true serious approach to resolving the existing grievances of the Palestinian people without the international community standing by its existing commitments to the resolution of the Palestinian situation we will never see a just peace and without that we cannot have true security in our region. We are all of one message on this and we hope that the international community will come together to support those ideals.”

UN Secretary General Antonio Guterres said the situation in the Middle East was “growing more dire by the hour”.

“Divisions are splintering societies and tensions threaten to boil over,” he said in his address to the UNSC.

“It is vital to be clear on principles,” he added, starting with the protection of civilians.

Guterres underscored the need for an immediate humanitarian ceasefire.